as we all knew Jrpg genre are really popular with teenage protag and party member , but recently i found xeno x cast or party member not entirely fill with teenager but it's almost made up by ... 

 doug age:30                       lao age :31 elma age : 29                             gwin age : 24          

        irina age : 27                     nagi age : 57 

only lin are 13 years old from blade organization and 1 native mira party member at 18 years old, then we have cristoph: 24 , HB: 29 , aksena :21 , boze :54 mardeth : 26 and fry : 30 , there are few unknown that's ru and ierv both looks past 20 judging by the appearances It's  refreshing to see entire cast are mostly consist of older or adult people that looks like an elite soldier rather than random teenager who going to save the world by power of frienship (lol)

i hope many developers will follow this route on jrpg genre 

Well I can make up numbers too. They all look 10 years younger.

the only people that looked their age is Doug and Nagi.

That's not how it works

Yes and the Bravely Default cast are 18 and older

now let's compare to other upcoming sci-fi jrpg

the cast/party that are going to save the world from star ocean 5 

Most look within an acceptable range for those ages. Exceptions for me being Irina and Gwin. They could both be 20 or so. The art direction is going to naturally skew things though.

Anyway I dont know what you mean exactly by recent but the FFXIII cast range between 14-40... 3 of them are 21, 2 are teens and Sazh is old

One thing I liked about Suikoden 3 was that two of the three protagonists were adults. Chris was a knight in her 20s and Geddoe was a mercenary who was like 100 but looked about 40 or so. Most of the potential party members were adults as well, I think.

then we have badass support character

ga derg and ga bow